Consumers have come to widely recognize and accept molded spouts as dispensing ports in packaging. One example, is the common gable top carton which is formed from a composite of paperboard and polymeric materials for the storage of, for example, liquid food products such as juice and milk. In an effort to provide maximum resealability of such packages, the industry has gone to using molded spouts mounted to the packages. These spouts can include threaded or snap-type, e.g., flip-cap, closures to provide maximum resealability of the package. These closures reduce the amount of degradation, i.e., spoilage, of the food product by reducing the exposure of the container contents to oxygen and airborne contaminants.
Known spout arrangements can also be used to provide tamper evidence or tamper indication as to whether the container has been opened, and the contents tampered with or altered in any way. In one known arrangement, a membrane is formed within the spout to seal the container contents from the environs. In order to access the container contents, the membrane must be removed from the spout. In one commonly used arrangement, a pull ring is formed as part of the membrane to facilitate removing the membrane from the spout.
While this arrangement has become accepted by the consuming public and has come into wide spread use in the packaging industry, there are a number of drawbacks. First, the membrane must be formed so that it is readily removed with a limited, predetermined amount of force required to pull the pull ring to remove the membrane. That is, the membrane must be sufficiently thin so that it can be readily severed and pulled from the spout. On the other hand, the membrane must have sufficient strength, generally correlative to thickness, so that it does not fracture or tear during, for example, mounting the closure to the package material or transport or the filled package, prior to initial use of the package.
Additionally, known spout-type packaging generally includes a tubular spout portion that extends upwardly from a flange that is mounted to the package. The membrane is formed intermediate the upper and lower ends of the spout, that is, of the flange and below the top end of the spout. In such an arrangement, the region between the membrane and the bottom of the spout, about coplanar with the flange, creates a pocket and thus an opportunity for bacterial growth, in that this pocket below the membrane can be difficult to sterilize.
Accordingly, there continues to be a need for closure spout barrier membrane that enhances the ability to pasteurize or sterilize the product, to maintain the necessary hygienic standards. Desirably, such a membrane maintains its integrity during the process of mounting the spout to the package, and is readily removable from the spout for easy access to the container contents.